Fresh water is a limited natural resource and using it efficiently is essential to insuring an adequate supply is available for future generations. Agriculture, industry, and domestic populations all compete for use of limited amounts of readily available fresh water, which is less than one percent of the Earth's total water, with the remainder being salt water or water frozen in the polar ice caps. Water conservation efforts are particularly important in areas in which increasing populations and affluence place new demands on the management of water supply and distribution. To be sustainable, the amount of water withdrawn from the environment cannot exceed its natural replacement rate.
Policies for managing water as a natural resource should also consider energy conservation. Utility companies and other facilities that pump, deliver, heat, and cool water, and those that treat waste water, consume a significant amount of a country's energy production.
About 10-15 percent of total water use in the US is for domestic purposes. The US Environmental Protection Agency estimates that the average family uses more than 300 gallons of water per day at home, with roughly 70% of this being indoor use. Among the domestic indoor uses of water, 24% are for toilets, 20% are for showers, 19% are for faucets, 17% are for clothes washers, 12% are due to leaks, and 8% are for other purposes. https://www.epa.gov/watersense/how-we-use-water The average shower uses about 17 gallons of water and lasts for about eight minutes. The average household in the US has 2.5 occupants which means that each day, about 40 gallons of water are used for showers per household. Over the course of a year, showers in the US account for 1.2 trillion gallons of water use. Showers are also one of the largest uses of hot water in the home and an electric hot water heater typically accounts for about 17 percent of residential electricity usage.
There have been many efforts to improve water and energy conservation for showers including shower heads that restrict the flow of water, hot water heater with greater efficiency, and the like. Despite these efforts, a significant amount of water and energy is wasted simply waiting for showers to warm up before being used. This invention satisfies this need amongst others.